(1) Field of the Invention
The present invention relates to an assembly and a method of use for producing a high velocity water jet in a deep-water environment where depth pressure would typically inhibit the formation of a supercavitation bubble.
(2) Description of the Prior Art
High velocity jets are commonly used in industrial systems for cutting operations. For example: pressures of 380 Mpa (50,000 pounds per square inch), generated with specialized hydraulic pumps, are used to produce small diameter fluid jets with velocities approaching 800 meters per second. These systems are designed for precision and continuous cutting. As such, diameters of the fluid jets are typically very small (no greater than one millimeter).
Jet pulses of this size can only penetrate a short distance (typically one meter) in the water. Power consumption for significantly larger jets becomes prohibitive if sustained operation is required.
The water jet system described in U.S. Pat. No. 6,868,790 (Gieseke et al.) is designed to overcome the jet formation inhibiting effects of water as a surrounding medium. The system and method of use of the cited reference utilizes a supercavity formed by an impulsively-created jet as a jet front propagates through the medium. At a significant depth (greater than one hundred meters) and under a high ambient pressure at the depth, the cavitation bubble, that would otherwise form at the jet front, is suppressed. For use in deep water drilling applications, a need therefore exists for forming the cavitation bubble that overcomes the jet formation inhibiting effects of water as a surrounding medium.